feat(updater): support updates after verified SeaweedFS migration

backend/src/modules/selfhost-updater.ts

@@ -36,6 +36,7 @@ const state = z.object({
 const plan = state.omit({ status: true }).extend({
     updateAvailable: z.boolean(), requiresComposeAdoption: z.boolean(),
     estimatedBackupBytes: z.number().nonnegative().finite().optional(),
+    storageProvider: z.enum(["minio", "seaweedfs"]).optional(), storageImageRetained: z.boolean().optional(),
     retiredServices: z.array(z.enum(["matrix-db", "matrix-synapse", "matrix-redis", "matrix-element",
         "matrix-livekit", "matrix-rtc-jwt", "matrix-turn", "matrix-well-known"])),
 });
@@ -48,6 +49,7 @@ const job = state.extend({ plan: plan.optional(), progress: state.optional(),
 const status = z.object({ apiVersion: z.literal(1), acceptingRequests: z.boolean(), engine: state,
     installed: state.pick({ version: true, revision: true }), request: job.optional(),
     capabilities: z.object({ requestLogs: z.boolean() }).optional(),
+    storage: z.object({ provider: z.literal("seaweedfs"), migrationPending: z.boolean() }).optional(),
 });
 const logs = z.object({ requestId, logs: z.array(z.object({
     source: z.enum(["service", "events", "commands"]), content: z.string().max(6000), truncated: z.boolean(),